Strainer or drum snare tensioning



Aug. 1, 195o C. H. STRUPE STRAINER OR DRUM SNARE TENSIONING MECHANISM Filed Aug. 9, 1946 Patented Aug. 1, 1950 STRAINER OR DRUM SNARE TENSIONING MECHANISM Cecil H. Strupe, Cleveland, Ohio, assignor to WFL Drum Company, Chicago, Ill., a copartnership Application August 9, 1946, Serial No. 689,383

4 Claims.

This invention relates to improvements in a strainer or drum snare tensioning mechanism v'and has for its main object to provide a simple, Vunitary mechanism of this type which includes a lever actuated means operable by the drummer` to tension and slacken the drum snares and which includes also anadjusting element for determining the maximum degree to which the snares may be tensioned by operation of the lever aforesaid.

A further object of the invention is to provide a combined lever actuated and maximum tension adjusting means, all of which are embodied in a unitary compact and light weight mechanism mounted upon the shell or casing of a snare drum, and wherein the actuations of the lever will not affect the means for adjusting the degree of tensioning of the snares.

= A suitable embodiment of the invention is illustrated in the accompanying drawings, wherein:

Fig. 1 is afragmentary perspective view of a snare drum equipped with a mechanism constructed in accordance with the invention.

. Fig. 2 is a central vertical radial sectional view, on an enlarged scale, showing a fragmentary part 'of the drum and the said mechanism mounted fthereupon.

' Fig. 3 is a fragmentary plan sectional view taken on the line 3 3 of Fig. 2.

Fig. 4 is a fragmentary plan sectional View taken on the line 4--4 of Fig. 2.

Fig. 5 is a fragmentary detail sectional view, on an enlarged scale, taken on the line 5 5 of Fig. 2.

Fig. 6 is a view in elevation, on an enlarged scale, of a non-rotatable collar of the mechanism.

Fig. '7 is an enlarged perspective view of the split spring washer employed.

The mechanism of this invention comprises a channeled bracket member l (Fig. 2) which is suitably mounted rigidly upon the shell or casing 2 of the drum between the ends of the latter in vertical alignment with the snares 3.

The latter are secured at their ends to plates 4, one of the latter being rigid with the shell or casing 2, and the other thereof being movable radially of the said casing.

In the instance illustrated, one of said plates 4 is movable through a slot 5 in the lower drum head tensioning hoop of the drum and is connected pivotally with the outer end portion of the channeled rocking lever 1, the side flanges of which are pivotally connected between their ends with the flanges of the bracket member I by means of a pivot element 8.

The other end of said lever I terminates in a cylindrical sleeve 9 extending perpendicularly of the web portion and tangentially of the flanges of said lever 'I with its axis substantially coincident with that of a screw threaded post IIJ projecting from and secured suitably against rotation to the drum shell 2 through the web of the channeled bracket member I in the upper end portion of the latter.

Said sleeve 9 is equipped with a helically disposed cam slot II of arcuate length appreciably greater than shown in Fig. 3 and which terminates in very shallow recesses I2a which operate to prevent the lever I2 from moving from either Vlimit of its movement otherwise than in response to manual actuation of a lever I2a.

Disposed over the said post I 0 is a helical compression spring I3 upon which a cylindrical sleeve I4 is supported, the latter being provided with a smooth cylindrical bore through which the shank of the post IG passes to constitute a bearing for the said sleeve I4.

The post I0 is provided with a key groove I5 to receive the key projection I6 of a washer I7 which bears normally upon the outer end of the sleeve I4 (Figs. 2 and 5).

A spring washer I8, shown in Fig. '7, is interposed between washer I'I and a sleeve nut I9 engaged with the post I0 and constitutes an adjustable stop member which limits the outward movement of the sleeve I4.

A spring 2l is disposed over the pivot element 8 and has its terminal arms 22 bearing upon the webs of the lever I and bracket member I, respectively, and operates to maintain the inner Wall of the cam slot II normally engaged firmly with the lever I2a secured rigidly to the sleeve I4 and projecting through the cam slot I I.

The spring I3 is normally under an appreciable degree of compression and its pressure against the sleeve I4 maintains the latter normally at the outer limit of movement and the spring washer I8 compressed against the inner end of the sleeve nut I9 which determines the outer limit of movement of said sleeve I4 to which the lever |211 is secured rigidly and removably.

The sleeve nut I9 is adjusted in position and cooperates with lever I2a and cam slot II to determine the degree to which the drum snares 3 will be tensioned when the end portion of the lever l, connected with said shares, is disposed at the outer limit of its movement. Said lever is moved to said limit responsively to swing of 3 the lever |2a upwardly from the position shown in Fig. 3.

Due to the fact that the post I is rigid with drum shell and that, therefore, the washer I1 cannot be rotated by frictional engagement with the sleeve I4, the sleeve nut I9 cannot be rotated by operations of 'the lever HCL-particularly also because of the relatively high pressure exerted upon the inner end of said sleeve nut I9 by pressure of the spring I3 against the sleeve I4, washer posed to 'the left-hand of vthe Adrun'lme'r and thus the lever I2@l moved Aby va `thrust movement vof Athe left-hand, but, if Adisposed diametricallyfopposite to ltliepositicn of `Fig. 3, the'leverfl Zamust be'actuated byfthe right-hand and pulledrtowa'rd the 'drummer to tension thev snares.

I'Ii-claim as "my invention:

#A snare tensioning `mechanism comprising a lever pivotally connectedbetween itsendswith rthe drum shell, one endof `said lever Vpivot'ally connected with'the drumfsnares, fa longitudinally `g'rooved threaded post rigidly securedto the drum 'shellland `projectingthrough said lever adjacent its other end, a sleeve mounted rotatably and slidingly upon *said post, al'sleev'ef'nut mounted upon the outer Vend of said post, 'a washer 'nonrotatably tand :slidingly mounted upon said 'post *between said nut* and said sleeve, `a compression :spring in'terpos'ed between 'the latter Aand the drum shell, La lever 'rigid 'with said sleeve, 'and 'a helical typeof 'cam slot inthe portion of the first-named lever adjacent to said sleevethrough "which `Jthe lever of the f latter projects.

a"sec`ond 'spring is 'engagedwith said first-'named lever and the drum shell 'to maintain said-lever 4 normally in snare slacking position and operative in cooperation with said sleeve operating lever and the cam slot to perform the functionv of said compression spring in event of breakage of the latter.

3. Mechanism of the type specied comprising -a channeled sheet metal rocking lever :pivotally mounted between its ends upon the drum shell and pivotally connected at one end with the drum 'snares and equipped at its other end with a wall extending perpendicularly to said shell and pro- Yvided lwith a helical cam slot terminating in extension portions extending angularly of said slot, a threaded longitudinally grooved post rigidly secured at one end to the drum shell and projecting at its Vother end through the outer wall of said lever, a cylindrical sleeve mounted rotatably and slidably upon said post, a lever secured rigidly to said sleeve and projecting through said cam slot, a sleeve nut engaged with the outer end of said post, 'a Washer non-rotatably'and slidably 'engaged with said sleeve-and interposed-between the latter and Asaid sleeve nut,` anda-compression fspring interposed between the said --sleeve and the drumfshell.

1l. 'A structure, `according to claim 3., wherein a channeled bracket ris secured rigidly I.to the 'drum shell 'andarpivotmember for the channeled lever Ipasses `through ysaid bracket, and a lV- shaped spring is mounted pivotally between its ends vupon said pivot `lneniberand has the outer 'ends of its arms-bearing upon thedrumshell and said last-named end portion of said channeled lever, respectively. A, n

CECIL H.

REFERENCES CITED The following references are ofrecord inthe file of this patent:

UNITED STATES PATENTS Number Name y Date n 389,053 rsmith ,May v26, I190s 1,354,028 Danly Spt. 28, 1920 v2,096,209 strupe i ot. 19, 1937 2,166,733 Slingerland July 1;8, y1,939 2,274,435 Slingerland Feb. (#24, 1942 

